通过 JOOQ-meta 访问 H2 元模型时出现 SQLException

SQLException when accessing H2 metamodel through JOOQ-meta

我正在尝试使用 JOOQ 获取我的 H2 内存数据库中所有表的列表 DSLContext.meta():

DSL_CONTEXT_PROVIDER.db().meta().getTables();

结果:

    java.lang.RuntimeException: org.jooq.exception.DataAccessException: Error while accessing DatabaseMetaData
        at MyTest.deleteEntities(MyTest.java:222)
        at MyTest.cleanupDatabase(MyTest.java:201)
        at MyTest.afterTestCase(MyTest.java:117)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:497)
        at org.junit.runners.model.FrameworkMethod.runReflectiveCall(FrameworkMethod.java:50)
        at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
        [... omitted for brevity ...]
    Caused by: org.jooq.exception.DataAccessException: Error while accessing DatabaseMetaData
        at org.jooq.impl.MetaImpl.getCatalogs(MetaImpl.java:160)
        at org.jooq.impl.MetaImpl.getSchemas(MetaImpl.java:168)
        at org.jooq.impl.MetaImpl.getTables(MetaImpl.java:179)
        at MyTest.deleteEntities(MyTest.java:210)
        ... 29 more
    Caused by: org.h2.jdbc.JdbcSQLException: The object is already closed [90007-174]
        at org.h2.message.DbException.getJdbcSQLException(DbException.java:332)
        at org.h2.message.DbException.get(DbException.java:172)
        at org.h2.message.DbException.get(DbException.java:149)
        at org.h2.message.DbException.get(DbException.java:138)
        at org.h2.jdbc.JdbcConnection.checkClosed(JdbcConnection.java:1410)
        at org.h2.jdbc.JdbcConnection.checkClosed(JdbcConnection.java:1388)
        at org.h2.jdbc.JdbcDatabaseMetaData.checkClosed(JdbcDatabaseMetaData.java:2963)
        at org.h2.jdbc.JdbcDatabaseMetaData.getCatalogs(JdbcDatabaseMetaData.java:756)
        at org.jooq.impl.MetaImpl.getCatalogs(MetaImpl.java:143)
        ... 32 more

DSL_CONTEXT_PROVIDER.db() 看起来像这样:

JdbcDataSource h2ds = new JdbcDataSource();
h2ds.setURL("jdbc:h2:mem:testDB;create=true");
h2ds.setUser("");
h2ds.setPassword("");
return DSL.using(new DefaultConfiguration().set(new DataSourceConnectionProvider(h2ds)));

普通查询在上述配置下工作正常,但 meta().getTables() 不行。如果我将 DataSourceConnectionProvider 替换为不关闭连接的匿名实现,则不会再抛出异常。

H2 似乎不赞成在关闭基础连接后对 connection.getMetaData() 返回的对象调用 getCatalogs() 等方法。这是 jooq-meta(我使用 3.7.0)中的错误还是我的配置有缺陷?

jOOQ 3.7.0 / 3.7.1 及更早版本在 org.jooq.Meta 中缓存 DatabaseMetaData。这是一个错误 (4762),很快就会修复。

您 运行 遇到此问题的原因是因为您使用的 DataSourceConnectionProvider 并非真正用于独立连接,或者 "simple" DataSources。它在每次查询后关闭连接(这通常转化为将其返回到池中)。关闭连接后,缓存的 DatabaseMetaData 引用已过时。

您已经记录了解决方法:不要将 "simple" DataSource 与 jOOQ 的 DSLContext.meta() API.

一起使用